1. Technical Field
The present invention relates to compact electro-statographic image reproducing apparatus. In particular, the invention relates to miniaturization of electro-statographic image reproducing machines that include a bypass paper-feeder for feeding specialized paper such as cardboard, OHP sheets, and surface-coated paper to the image reproduction section of the machines.
2. Description of Related Art
In electrostatographic image reproducing devices such as photocopiers, printers, and facsimile devices, miniaturizing is desired to reduce space requirements in offices. Typically, a plurality of sheet-feeding cassettes housing sheets are arranged in copiers according to sheet sizes used, and each sheet-feeding cassette can be inserted into and withdrawn from the machine.
Photocopying machines furthermore typically comprise a document table on which original documents for copying are loaded, provided on the upper surface of the copier. Light is shone on sheets loaded on the document table, and light reflected from these originals is converted into electrical signals by a CCD sensor or the like. The signals from the CCD sensor are used to reproduce a corresponding electrostatic latent image on the surface of a photosensitive drum in the copying machine. This electrostatic latent image is developed by a developing device within the machine to form a toner image. Then, the sheet superficially bearing the toner image is sent to a fixing device, also arranged within the machine, where the toner image is heated and fuse-fixed to the sheet.
The sheets generally used in electrostatographic image reproduction are sizes B5, B4, A4, and A3. Often, the size of the document table is made to accommodate the largest among these, A3-size documents, so that an entire A3-size document can fit on the table. Further, in the majority of cases, the sheet-feeding cassette installation section, into which the sheet-feeding cassettes are installable/removable, can be fitted with a sheet-feeding cassette that can hold A3-size paper.
Sheets drawn out from the sheet-feeding cassette installation section are transported to the image reproduction section through a sheet-feeding transport path. Sheets onto the surface of which a toner image has been transferred in the image reproduction section are sent through a discharge transport path to the fixing device, from which they are discharged to a discharge tray.
Herein, by disposing the document table and the sheet-feeding cassette installation section vertically such that they are approximately stacked from a plan aspect, and by configuring the positions of the sheet-feeding transport path, the image reproduction section, the discharge transport path, and the fixing device so as to make the sheet-transport direction perpendicular, a copying machine can be provided for which the installation area is only slightly larger than A3 size.
Herein, sheets drawn out from the sheet-feeding cassette make a sharply switching turn when transported along the vertically extending sheet-feeding transport path. Therefore, using specialized paper such as cardboard, OHP sheets, and surface-coated paper with this type of sheet-feeding cassette is difficult. Consequently, configurations are known in which a bypass tray capable of housing specialized paper is installed, with a bypass transport path constructed such that sheets transported from the bypass tray to the image reproducing section are not turned sharply.
In the image reproducing apparatus described above, ordinarily, the bypass tray is provided projecting from the side of the apparatus. In using this bypass tray, the sheets are loaded into the bypass tray projected from the side of the device. An input panel is used to designate the bypass tray as the sheet-feeding position from which sheets are to be supplied, and the start button is pressed.
Accordingly, in this type of image reproducing apparatus, the bypass tray juts out from the side of the apparatus main body. Thus, the actual installation area is made larger than the area occupied by the apparatus main body just by the size of the bypass tray.